1. Field of the Invention
This invention relates generally to shoe upper forming machines, and more particularly, is directed to size adjustment mechanisms on a machine for performing a pulling and lasting operation on the forepart regions of a shoe.
2. Prior Art
Certain problematical areas of shoe lasting, include the quality lasting of welt shoes, where, during the lasting operation, a particular limited movement of the wipers is required so that the upper will be pressed uniformly against the insole rib without damaging the insole rib by bending it excessively or otherwise misaligning the rib. A mechanism to help alleviate the problem of excess wiper motion at least to the sides of flat lasted shoes has been shown in U.S. Pat. No. 3,196,470 to Bowler, and is assigned to the assignee of the present invention. The mechanism shown in this patent is directed towards the "initial" position of each wiper to permit lasting of particular contoured soles, by utilizing therewith a plurality of adjustable knobs and linkages. It does not direct the invention to controlled displacement of the ribs of a welt insole, to allow known counteraction of the pulling on the ribs after the wipers are removed. The controlled displacement of the ribs in an inward direction is necessary to neutralize the afterwipe outward pulling forces to thereby prevent any outwardly pulled ribs on the insole from otherwise getting in the way of the stitching needle.
It is an object of the present invention to provide a mechanism which will permit the exact preselecting of the rotational distance of travel of the wiper head and associated wipers and stopping of that rotational motion against the toe and side portions of a shoe being lasted, to permit a controlled displacement of the ribs of the insole on the shoe being lasted.
It is another object of the present invention to simplify the mechanism required to limit and govern the motion of the toe and forepart lasting wipers on a lasting machine.
It is a further object of the present invention, to provide a more exacting mechanism which will permit quality lasting on the margins of welt shoes.